Austin, Texas -- To 15-year-old Andrea Hernandez, the tracking microchip embedded in her student ID card is a "mark of the beast," sacrilege to her Christian faith - not to mention how it pinpoints her location, even in the school bathroom.

But to her budget-reeling San Antonio school district, those chips carry a potential $1.7 million in classroom funds because Texas school funding is based on daily attendance.

Starting this fall, the fourth-largest school district in Texas is experimenting with locator chips in student ID badges on two of its campuses, allowing administrators to track the whereabouts of 4,200 students with GPS-like precision.

Hernandez's refusal to participate isn't a twist on teenage rebellion, but has opened a debate over privacy and religion that has forged rare like-mindedness between typically opposing groups.

When Hernandez and her parents balked at the so-called SmartID, the school agreed to remove the chip but still required her to wear the badge. The family refused on religious grounds, stating in a lawsuit that even wearing the badge was tantamount to "submission of a false god" because the card still indicated her participation.

On Wednesday, a state district judge is expected to decide whether Northside Independent School District can transfer Hernandez to a different campus.

"How often do you see an issue where the ACLU and Christian fundamentalists come together? It's unusual," said Chris Steinbach, the chief of staff for a Republican state lawmaker who has filed a bill to outlaw the technology in Texas schools.

The concept isn't new, but hasn't exactly caught on nationwide. In 2005, the American Civil Liberties Union raised concerns about a similar initiative at a California school. That same year, a suburban Houston school district began putting the chips in its student IDs, and served as the blueprint for Northside's pilot program.

Ronald Stephens, executive director of the nonprofit National School Safety Center, said he didn't believe the technology to be widespread but predicted "it'll be the next wave" in schools. The chips use radio-frequency identification transmitters and only work on campus.

The Northside school district spent roughly $261,000 to equip students at one high school and one middle school with SmartIDs, a decision made with safety and efficiency in mind, said district spokesman Pascual Gonzalez. Imagine quickly accounting for students in the event of a lockdown, he said.